Ahn Hun-cheol has been sleepless for several months as he fine-tunes the audio system for the World Cup opening ceremony to be staged in Sangam Stadium, Seoul May 31.

"Imagine that a speaker fails at the moment the president declares the opening of the World Cup. What if there is speaker trouble while several billion people around the globe are watching the ceremony? It really makes me sleepless," said the Daiyoung Corporation deputy manager.

Ahn handles the acoustic quality of 16 large speakers to be installed on the ground for the opening ceremony and works hard to present the audience with a complete surround sound experience. The audio system for the ceremony is a theatre sound system that outputs different types of sound at each speaker. When one speaker delivers speech, for instance, a second delivers music while a third produces effects.

Because a sound is delivered to speaker in digital method, the chances of feedback are zero. Each speaker's output is 11,200W, 100 times greater than the average home system.

"In the opening ceremony, an acoustic system manager’s major responsibility is to put all the speakers away in just three minutes because the opening match between France and Senegal begins right after the 30 minute-opening performance. Each speaker has wheels but running with a 550kg speaker is not easy,” said Ahn, who was entrusted with the responsibility by KOWOC in last November.

He says a prayer for the opening ceremony free of raindrops whenever he goes to bed because rain and speakers don't mix.

(Ahn Yong-hyeon, justice@chosun.com /photo=Chung Kyeong-ryeol, krchung@chosun.com )